This is why you lost your coins.

Frequently scammers will create a website that looks identical to the real site.  Then they will create an address that looks VERY much like the real addres (for example e1ectrum.org instead of electrum.org). Then they will pay for advertisement for their website with Google's ad service.  Google always shows paid ads BEFORE search results.  Therefore, the scam site is the "first site after a google search".  You click on the link and it looks exactly like the Electrum site.  You download the software and it looks exactly like the Electrum software.  You import your seed and it immediately sends your seed to the scammers without you knowing.  The scammers have software that receives the seed and immediately creates a transaction to steal the bitcoins.  Then you shut down your wallet and don't know about it until the next time you open it and the transaction stealing your bitcoins is already confirmed.

Unfortunately, there is nothing you can do to get your bitcoins back from the thieves.